Tartaric Acid-Assisted Precipitation of Visible-Light-Driven La-Doped ZnO Nanoparticles Used for Photocatalysis of Methylene Blue

Abstract

Abstract: ZnO nanoparticles with and without La dopant were prepared by a tartaric acid-assisted precipitation method at room temperature (TR) and followed by high temperature calcination at 600°C for 2 h. The as-synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). In this research, the samples with and without La dopant were pure phase of hexagonal wurtzite ZnO nanoparticles. The particle size of ZnO was decreased with increasing in the content of La dopant in ZnO samples. Photocatalytic activities of ZnO nanoparticles doped with different contents of La were tested for photodegradation of methylene blue (MB) under visible light irradiation. The 3% La-doped ZnO sample has the best photocatalytic activity of 97% under visible light irradiation within 100 min because the recombination of electron-hole pairs was suppressed and efficient charge separation was enhanced by La3+ dopant.